When a series of data (transaction) in an arbitrary process is transmitted from a transmission source to a transmission destination, the transaction is divided into packets and transmitted. If there are multiple transactions, respective packets of the transactions are transmitted in a prescribed sequence. For example, for transactions A and B, the prescribed sequence may be an alternating transmission of 1 packet of transaction A and 1 packet of transaction B.
Further, a conventional technology related to packet transmission evaluates network quality. For example, according to the conventional technology, the flow of communication between communication terminals is subject to measurement and extracted from packet header information. The conventional technology estimates network communication quality that includes information related to packet loss on the network, based on header information inclusive of a packet sequence number and from time series information concerning packet arrival at the receiving apparatus. For examples, refer to Japanese Laid-Open Patent Publication No. 2005-210515, Japanese Laid-Open Patent Publication No. 2001-111608, Japanese Laid-Open Patent Publication No. 2008-17407, and Japanese Laid-Open Patent Publication No. H6-152648.
Nonetheless, with the conventional technologies above, delay related to a transaction for which a packet that, according to the prescribed sequence, should have been transmitted from the transmission source device has been skipped, is difficult to determine. Consequently, the time involved and the burden on the verification engineer to identify the cause of the transaction delay with respect to the transmission source device is enormous, arising in a problem of long verification periods.